For articles (examples of the articles encompasses shaped products (i.e. products having been processed to have desired shapes) such as metal products, plastic products, inorganic products, wood products and the like), coating (painting) process to form a coating film on the articles (shaped products) is carried out in some cases, in order to give the article durability and/or aesthetic property including hues. The articles to be coated (hereinafter, referred to as coating-target articles) are various in terms of their materials, shapes and the like. In view of this, spray coating, dip coating and other coating method are widely used because it is relatively easy by using these methods to form the coating film in accordance with complicate shapes of the coating-target article, and to form the coating film in bag-shaped sections (cave-shaped sections) and/or gaps of the coating-target article.
In general, the coating film formed by coating (painting) the coating-target article is laminate film including a plurality of layers. For instance, the laminate film includes (a) a base film for giving the laminate film adhesiveness and anticorrosiveness so as to allow the laminate film to be adhered on a surface of the coating-target article and to protect the coating-target article from being corroded, (b) a finish-coat film for giving the coating-target article aesthetic appearance, (c) a protective film for protecting the finish-coat film, and/or (d) the like layer. Therefore, in case where the spray coating or the dip coating is applied, a step (coating step) of coating the coating-target article with paint by spraying the paint onto the coating-target article or dipping the coating-target article in the paint, and a step (fixing step) of fixing the paint on the coating-target article by drying or baking are repeated in turn in order to form the respective films of the laminate film.
The spray coating and the dip coating, which are multi-staged process in which the coating step and the fixing step are repeated in turn require a large coating site in which a long process line is constructed for the multi-staged process. Moreover, because the coating step and the fixing step are carried out in multi stages, the process management is complicate. Further, the multi-stage process causes a large consumption of a volatile material in the coating step and the fixing step, and requires a large amount of energy to repeat the coating step and the fixing step.
Therefore, it is difficult to solve or achieve the followings problems or required improvement in the coating process using the spray coating or the dip coating. The problems and improvements are: need of securing the coating site; need of improving cost performance by reducing maintenance cost for coating and drying, alleviating smell of the volatile material, and reducing a volatilized amount of the volatile material, and the like improvement; need of attaining easy management for the coating process; need of reducing the energy consumption; and the like needs.
As a coating method for realizing the improvement in cost performance, easy management of the coating process and the lower energy consumption, Publications of Japanese Patent Applications, publication Nos. 2000-79796 (Tokukai 2000-79796; published Mar. 21, 2000), and 10-58895 (Tokukaihei 10-58895; published on Mar. 3, 1998) and the like publication, for example, teach so-called film decoration method in which the coating-target article is coated with a laminate film which comprises a plurality of layers in lamination. In the film decoration method, the laminate film is placed on the surface of the coating-target article with no space therebetween so as to coat the coating-target article. Therefore, the film decoration method requires no multi staged coating process unlike the spray coating, dip coating and the like coating methods. Moreover, the process of the film decoration method is easy to manage and has lower energy consumption.
Meanwhile, it is required for the laminate film that it have properties (hardness, non-stickiness, solvent resistance, chemical resistance and other properties; hereinafter referred to as “coating film properties) realized in the spray coating, dip coating, and like, and that it have ornamental property (property to give the coating-target article a decorative appearance) and processability (property to enable appropriate decoration of the coating-target article). Here, the ornamental property includes: a shining appearance that indicates how shiny (twinkling) the laminate film is when the coating-target article is decorated with the laminate film; light scattering property of the laminate film when the coating-target article is decorated with the laminate film; flip-flop property that indicates a contrast between a highlighted look and a shaded look of the laminate film when the coating-target article is decorated with the laminate film; and other property. Moreover, the processability includes: traceability (shape-tracing ability) for a shape of the coating-target article; reproducibility for the 3-dimentional shape of the coating-target article; easy handling such as easiness in winding the laminate film; and other property.
However, the conventional laminate film has a difficulty to attain the processability and ornamental property as well as the coating film properties: the conventional film with high coating film properties is poor in the processability and ornamental property: likewise, the conventional film with high processability has a problem in the coating film properties and the ornamental property.
More specifically speaking, if the processability of the laminate film is to be improved, it is necessary to give the laminate film flexibility so that the laminate film can trace the shape of the shaped product (coating-target article). The flexibility can be attained by preparing the laminate film with a resin having a low glass transition temperature, by reducing the cross-linking density of the laminate film, or by the like.
However, if the laminate film is improved in flexibility, it becomes difficult to attain the coating film properties of the laminate film. Moreover, it becomes easy to disorder an array of a light scattering material or the like that gives the laminate film twinkling sensation and flip-flop property. Thus, it becomes difficult to attain the ornamental property.
As described above, there are such problems for the conventional film decoration method that when the processability necessary for decorating the coating-target article with the laminate film is attained, it is difficult to attain the coating film properties and the ornamental property equivalent to these attained in the spray coating, dip coating, and other coating methods.